We report an experimental study of the dispersion of a passive tracer in the two-dimensional inverse energy cascade, which shows that a nonintermittent velocity field can sustain a strongly intermittent concentration field. The experiment suggests the exponents of the intermittent concentration field saturate at large orders towards ${\xi }_{\infty }\sim \mathrm{1.2.}$ These observations are in excellent agreement with a recent numerical work [A. Celani, A. Lanotte, A. Mazzino, and M. Vergassola, Phys. Rev. Lett. 84, 2385 (2000)] and theoretical expectations [E. Balkovsky and V. Lebedev, Phys. Rev. E 58, 5776 (1998); V. Yakhot, ibid. 55, 329 (1997)].

• Received 16 June 2000

DOI:https://doi.org/10.1103/PhysRevE.64.035301